Roku stuttering with libmatroska MKV with DTS audio

A bug in the firmware of some Roku devices causes stuttering or skipped frames when the Roku tries to directly play an MKV with DTS audio, if the file was made with libmatroska.

Users have figured out a workaround: Remux the MKV with something other than MKVToolNix/libmatroska. FFmpeg works fine, for example:

ffmpeg -i in.mkv -map 0 -c copy out.mkv

No stuttering with this output file. What does libmatroska do differently than FFmpeg when writing the MKV? Is there a way to force MKVToolNix to write that same kind of file? And is there something special about DTS? Other audio formats work fine.

(There’s speculation in the linked discussion that it has to do with tags, but it doesn’t; I used mkvpropedit to add the same kind of tags as FFmpeg and it made no difference. Only fully remuxing with FFmpeg helped.)